The present invention concerns a method and apparatus for counting and packing solid foods having an undetermined shape, irregular; wet, adhesive, and soft surfaces; and that are easily broken.
In the field of production engineering for processed food, instrumentation and unmanned operation of the process is still undeveloped. In particular, there is a great difficulty in handling small amounts of solid foods with an undetermined shape; irregular, wet, adhesive, and soft surfaces; and that are easily broken.
Problems in measuring, counting and packing quite frequently appear in new product development and with frozen foods. The current trend toward using more highly processed, simple and easy-to-cook products has led to increased use of small amounts of various seafoods and vegetables as ingredients.
However, because most of these ingredients are flexible and with uncertain shape, they are easily damaged by mechanical processing, and moreover, they often become viscous and stick to food processing machinery, making it difficult to convey or to precisely hold the ingredients by the machinery.
Therefore, there are many food products that must depend on manual operation which leads to high manufacturing costs. According to the prior art, it is possible to separate a predetermined number of objects, line up these objects in order, and pack desired objects from among an abundantly supply of solid objects, not limited to foods. Transportation through the packing process is usually by a device including vibrating feeders and/or a belt conveyor and a guide. The number passing are detected with a photo sensor or pictorial image sensor. This technology is employed widely in fields such as counting electron parts, industrial parts, tablets, or pellets.
This technology is also typically used in the foods industry for counting and packing confectioneries such as nuts or dried fruits, dried eggs, dried meat, or dried Kamabokoes that are attached to instant noodles such as xe2x80x9cKayakuxe2x80x9d. (Kamaboko is the fish paste that is pasted on to a Japanese cedar before steaming, and the cedar plate is separated before cooking.)
However, in the case where the solid foods have sizes and shapes that are not uniform, many problems frequently occur such that the conveyed solid foods are piled up without being separated one by one leading to intermittent blockages.
In addition; current conveyance technology includes controlling an attenuation of oscillation so as to regulate the conveying little by little when the counted number approaches a value predetermined to maintain a the precise number of packed items. However, this technology is unsuitable for packing only a few pieces leading to a fluctuation of packing time.
Furthermore, when the solid foods are wet and viscous, of the mechanical feeder and/or the solid foods sticks to each other, and stable transportation cannot regularly be achieved.
Various kinds of breakthrough are proposed in order to solve these problems. For example, JPA53-518 74 discloses an invention in which solid foods are separated one by one with an adsorption pad that is provided with a rotating drum. After being released by compressed air, the foods are counted in a chute section, and when the quantity reaches a predetermined value, a shutter opens.
JPA09-12143 discloses an invention in which solid foods are similarly separated one by one with an adsorption aperture provided with a rotating drum. The food items are peeled apart and aspirated by a jet air nozzle or an suction nozzle installed proximate to the drum, the food items are counted, and when the quantity reaches a predetermined value, the compressed air is stopped.
In addition, Japanese Laid-Open Utility Model No. 07-23739 discloses an invention in which solid foods are separated one by one with the adsorption aperture provided with a rotating drum. Here, the food items are peeled apart when they reach to an air shield board installed proximate to the drum, and then they are counted by a photo sensor.
These conventional teachings are effective for separately counting and packing, one-by-one, solid foods of uncertain shapes being conveyed at random. However, because these teachings require the solid foods to touch the adsorption aperture of the rotating drum in a predetermined home position, it is necessary to supplement these operations with other steps such as dropping the solid foods from an upper side of the rotating drum, or vibrating intensely the food items on a lower table. These conventional machines are unsuitable for solid foods prone to crumbling or generating powders or for solid foods, like frozen products, that easily break or crack. In addition, the solid foods may not be regularly adsorbed by each adsorption aperture provided for the drum, and because the procedure counts up from zero to the instruction value, the time required until the predetermined number of solid foods are finally packed will fluctuate. These fluctuating times are detrimental because, when a downstream process works with predetermined time interval, there are cases where the timing these two processes can not be synchronized.
On the other hand, there is a method for adsorbing, counting and conveying objects by an arm comprised one or plural of vacuum adsorption apertures. This method is a conventional technology that has been mainly used for gripping, transferring, and counting such parts with fixed form precisely positioned in the timing of being adsorbed as IC tips, wafers, or boards.
In this second conventional technology, the counting is executed by detecting an actuation frequency crossing the working space by the arm. Counting value is calculated on the premise that holding of the object by the vacuum adsorption aperture attached to the arm is complete. This technology is better at counting and packing or fixing easily breakable objects into a specific place within a designated time. However, this technology is limited to objects are dried, have fixed forms, and where the holding of the object by the vacuum adsorption aperture is precise. Therefore, in the case where the objects are solid foods with uncertain shape of which the vacuum absorption state is not stable and preparatory segregation positioning is difficult, this method is not applicable without any improvement because the possibility of an adsorption mistake is very high. Regarding the above-mentioned arm and nozzle procedure, some improvements using sensors have been proposed.
JPA60-54499 discloses a process of repeating the packing operation until the counting number reaches to the predetermined value while detecting whether a tip is safely adsorbed or not, where the tip number is determined directly by a pressure sensor in a negative pressure path.
JPA07-169819 discloses a process of repeating the vacuum adsorption operation until the counting number reaches the predetermined value of wafers in a case is appropriate, while detecting vacuum pressure to determine whether the state of adsorbing the wafer is safe or not.
However, even with these inventions are applied to the arm and nozzle technology, the time required until the predetermined numbers of the objects are finally packed fluctuates if an adsorption mistake happened. Meanwhile, a technology enabling synchronization with the next downstream process is disclosed in JPA5-229514.
JPA5-229514 discloses a process for a) detecting the weight of a conveyer bucket in a measuring station after a transfer of fruit pulp pieces, such as mandarin orange, a pine, and Megalobatrachus japonicas peach, to the conveyer bucket by a plurality of vacuum nozzles, b) identifying a conveyer bucket having a vacancy or a weight equal to a predetermined number of objects, and c) correcting the feed of the vacant conveyer bucket from a downstream replenishment line, thereby ensuring the predetermined number of objects are packed. This invention is effective in the case where it is not necessary to pre-position the object; and where the object is soft, and having moisture and adhesive surface. However, because the counted value is calculated by weight differentiation processing, precise counting and packing of predetermined number becomes difficult in cases where there are large weight variation in the objects and where several kinds of the foods are necessary to be filled in one container. In addition, the invention needs large line constitution, and only the transfer machine unit is unable to count and pack the objects.
Thus, as described above, when treating solid foods having an undetermined shape, irregular; wet, adhesive, and soft surfaces; and that are easily broken with conventional counting and packing devices, manual pre-positioning and sort transportation of the objects were necessary. Also, it is difficult to precisely count and pack several predetermined numbers of the object in one cycle within a time interval settled for the purpose of synchronization with the next process.
The present invention solves the above mentioned weak points in a counting and packing apparatus by combining a vacuum nozzle and an adsorption confirmation sensor together by providing a method and apparatus for counting and packing the solid foods having an undetermined shape, irregular; wet, adhesive, and soft surfaces; and that are easily broken, without requiring manual pre-positioning and sorting, thus enabling speedy and precise counting and packing of a predetermined numbers of the solid foods within a predetermined time interval.
In order to achieve the above described purpose of counting, transferring, and packing solid foods one by one via adsorbing with a vacuum nozzle, the present invention provides a method for counting and packing solid foods comprising arranging N+xcex1 vacuum nozzles, optionally counting and selecting plural numbers of the vacuum nozzles corresponding to the predetermined packing number N from among the N+xcex1 vacuum nozzles where adsorption holding was ensured by an output signal from an adsorption confirmation sensor, and, after having conveyed the solid foods to a predetermined packing location, the predetermined packing number N of the solid foods are precisely counted and packed within 1 cycle by breaking the vacuum of the selected vacuum nozzle.
Moreover, the present invention is directed to an apparatus for counting and packing solid foods, comprising a table device configured to hold the solid foods to be counted and packed; N+xcex1 vacuum nozzles, each of said N+xcex1 vacuum nozzles including a flexible vacuum pad and an adsorption confirmation sensor; an arm holding the N+xcex1 vacuum nozzles, said arm displaceable horizontally in a right and left direction and vertically in an up and down direction, said arm configured to adsorb and convey the solid foods from the table device to a packing device, a vacuum source connected to the N+xcex1 vacuum nozzles by a respective vacuum breaking channels, and a control instrument configured to execute a control sequence and to break a vacuum of a specified vacuum nozzle, wherein N is a predetermined number of solid foods to be packed, and N and xcex1 are integers greater than or equal to 1.